Means for sheathing excavation walls



Ju 23, 1940. E. B. Down 2,188,077 MEANS FOR sHEATHING'ExCAvATIoN WALLS Filed May 16., 1958 3 Sheets-Sheet 1 mlu f EDMUND B. Down Jan.23,194o. E B Down 2,188,071

MEANS FOR SHEATHINGr EXCAVATION AWA-LLS Filed May 16, 1938 3 Sheets-Sheet 2 EDMUND B. Down Jan. z3, 1940.

3 Sheets-Sheet-S E. B. Down MEANS FOR SHEATHING EXCAVATION WALLS Filed May 16, 193s y E D EDM'UND B. DowD Patented Jan. 23, 1940 UNITED ASTATES MEANS FOR SHEATHING EXCAVATION WALLS Edmund B. Dowd, Homewood, Ill., assignorto Thomas L. Dowd, Chicago, Ill. l

Application May 16, 1938, Serial No. 208,164

9 Claims.

l' as trenches, for the underground installation of sewer pipes', water pipes, electrical conduits and the like, the manner of bracing and reinforcing the trench side walls to prevent caveins. has constituted a more or less make-shift arrangement which was relatively expensive and wasteful, and could not with impunity be relied upon either to prevent trench failures or to safely protect the men working in the trench.

In the past, vit has been the custom to utilize long planks of relatively narrow width for sheathing the trench or other excavation walls. These planks were sharpened at their lowermost ends, placed with their edges abutting, and driven into the earth as the digging of the excavation proceeded These planks were laterally braced by wales which formed abutments for beams or jacks placed across the trench and extending from one wall 'to the other thereof. The driving of these planks not only tended to weaken them, but not infrequently damaged them to such an extent that'they became practically use#A less and could not be used again.

Moreover, Whenever the planks were being driven, the associated jacks or snoring had to be loosened or removed.

This driving procedure necessitated that the upper ends of the planks should extend above the top of the trench. As 'a result, the protrude ing ends formed an objectionable barrier or im-v pediment at the top of the trench which interfered with the removal of dirt in` hand-dug trenchesI and seriously impeded the work in general of the men. Of course, when the trench had been dug to the desired depth, the protrud` ing ends of these planks could be sawed olf, sov as to have their uppermost ends evenly disposed. While this was satisfactory insofar as itremoved the impediment or barrier, such practice Awas indeed wasteful, since the sawed-ofi ends had f little value and this operation reduced the salvage valueof the planks.

It was the usual practice in 'constructing trenches in this manner to Aretain the planks in place until the trench was built, after which they were pulled by means of a pipe or other suitable member which could be used as a lever. By the use of a chain looped around a plank and secured to the lever, successive bights could be taken on the'plank, thus enabling it to' be sitated the use of extra men and labor and consumed a great amount `of time which might otherwise be utilized in more productive Work.

From the above, it will be appreciated that such procedure was at the outset Yvery inemcient and costly.

Having in mind the diiiiculties and objections encounteredin constructing a trench in the usual manner as described above, the present invention' contemplates an improved means for sheathing an excavation wall which may be easily applied to the wall as the digging progresses without disturbing the earth adjacentv thereto, which is eicient in operation, which causes a minimum of interference with the workmen, and which is thoroughly reliable and safe.

In practice, I have found that the cost of a trench, constructed by the methods usually em ployed, can be reducedv approximately 40% to 50% when my improved means are utilized.

A further object of the present invention is to provide an improved means for the purpose described,`wherein light,strong material, such as plywood, may be successfully used in such manner as to have a -high salvage Value, and which will enable the material to be used over again as successive portions of the excavation are being constructedor, if desired, the material, due to its relatively light weight, may be readily and easily transported to some other location for further use.

A further object of the invention is to provide an arrangement 'of the character described which utilizes standardized constructional units, which may be easily assembled in place with a minimum expenditure of timeand labor, and which when so assembled offers little or no interference with the construction work being carried on.

Another object of the invention is to provide in such an arrangement utilizing standardized constructional units, novel means for indicating the proper placing of the units to secure the most efcient results, thus enabling the work of sheathing the excavation wall to be carried on by unskilled labor.

A further object is to provide in an arrangement of the herein described character an improved sheathing arrangement in whichk the load forces on the sheathing members will be equalized or balanced, whereby the sheathing will at no time be dangerously overloaded or stressed.

It isfalso an object of the invention to provide an improved sheathing arrangement which will enable thev sheathing lto be removed from to the the bottom upwardly as the filling of a trench progresses.

A still further object is to provide an improved sheathing and scaiolding arrangement for use in the construction of trenches and the like.

Still another object is to provide improved means for supporting tile, pipes, conduits and the like at the bottom of a trench from the sheathing member, particularly where quicksand and bad ground are encountered.

Other objects and features oi the present invention will more fully appear from the following detailed description taken in connection with the accompanying drawings which illustrate several embodiments thereof, and in which:

Figure 1 is a plan view looking into a trench having Wall sheathing applied in accordance with the present invention;

Figure 2 is a transverse sectional view of the same, taken substantially on the line II-II of Figure l;

Figure 3 is an isometric view of the sheathing arrangement as it appears when facing one wall of the trench; this view disclosing a preferred and modified arrangement for applying pressure against this sheathing;

Figure 4 is a similar view of a further modied sheathing arrangement and means for applying pressure thereagainst; and

Figure 5 is a detail sectional view, taken substantially on the line V-V of Figure 4.

As shown on the drawings:

Although it will be appreciated by those skilled in the art that the present invention may be utilized in connection with various and sundry types of excavations, it has been endeavored in the present instance to describe the invention in connection with the construction of a trench such as might be dug for the underground installation of sewer pipes or other conductors.

In the digging of a trench, the trench is dug the desired width and side walls HJ and II are formed. When the depth of the trench has progressed a sufficient amount, a course of panels I2 are horizontally disposedA in surface engagement with each side wall of the trench, these panels being in end to end relation. The panels on each side of the trench are similarly disposed, and the joints between the adjacent ends of the respective panels on one side of the trench are directly opposite the corresponding joints on the other side of the trench.

The panels I2 are preferably formed of a plywood material which is rendered waterproof by any suitable treatment for this purpose. I have found that parailin oil and waterproof glue are satisfactory. The use of plywood for this purpose enables the utilization of relatively large areas of contact, and the material is somewhat exible and will readily conform to small irregularities in the trench wall. Moreover, due lightness of the material, it may be easily transported and moved from one location to another. In order to enable pulling of the sheathing panels from the trench and` handling them, each panel is provided adjacent its corners with an aperture I3 adapted to receive a hook or other pulling means.

The sheathing panels are forced against the trench wall by means of pressure applying pads, which in my preferred construction are formed as units generally indicated at A. The pressure applying pad A comprises a square plate or panel I4 which is also constructed of plywood and is of the same width as the panels I2. The plate I4 is likewise provided at each corner with an aperture I5, by means of which it can be pulled in the same manner as the panels I2.

Overlying one surface of the plate I4, there is secured as by nailing or the like a rectangular block or panel I6 and a similar block or panel I'I. It will be noted that the blocks I8 and Il are of less width than the block I4- and have their side edges and one end edge inwardly disposed relative to the associated edges of the block I4. Moreover, the panel I'I is of .less width than the panel I6. The panels I6 and I7, however, project outwardly over one edge of the block I4, as shown vin the installation illustrated in Figure 3. In this case, the uppermost ends of the blocks I6 and Il project above the uppermost edge of the block or panel I4. The purpose of these projecting ends of the blocks I 6 and Il will subsequently be apparent.

In my improved arrangement, the blocks I 4, IIi and I'I are assembled and secured together to form a unitary construction. This assembly is symmetrically disposed over the joint formed by. the adjacently disposed ends of the panels I2 and may be temporarily securedin position as by means of suitable nails driven through the block I4 into the associated panels I2.

For bracing the side walls of the trench, however, suitable shcring members or jacks, as shown at I8, are utilized, the respective ends of the jacks being disposed respectively against the inner surfaces of the block I l of the pressure applying y pads disposed on opposite sides of the trench.

In order to be able to similarly locate the ends of the jacks I8 with reference to their associate pressure applying pads, I provide a plurality of aligned shallow recesses I3 in the exposed surface of the block Il. This arrangement of indi'- cation also enables the utilization of a plurality of jacks in connection with any set of pressure applying pads, and when the ends of the jacks are located at the recesses, the jacks will be properly spaced and in parallel alignment. It will be noted that each side edge of the block I4 is provided at its midpoint with a V-shaped notch 20, and that the projecting ends of the blocks I6 and II are likewise provided, at the midpoints of their end edges, with similar notches. These notches are for the purpose of aligning the pressure applying pads with reference to the joints between the associated panels I2-,-I2. For example, the pressure applying pad may be disposed with any one of its edges uppermost, and by disposing the notch in that edge so that it is directly over the associated joint, the pressure applying pad will be symmetrically disposed relative to the joint.

liliv It will be noted that the pad unit is of greater thickness at its center, and due to the different widths of the blocks I "I, I6 and I II, this thickness is progressively decreased in a step by step manner outwardly towards the periphery of the block I 4. With the pressure applied by the jacks I 8 at the joints between the panels I 2-I2, there would be a natural tendency for the panels to bow outwardly into the trench. However, the outward bowing of the panels I?. is equalized by the cantilever action of the pressure applying pads which transmit pressure over marginal areas of the panels adjacent the joints formed by the adjacently disposed ends thereof.

At the right-hand portion of Figure 3 there is disclosed a modified form of pressure applying pad.

It will be noted that this pad assembly differs from that previously described by making 75 the block I6 of substantially square construction rather than rectangular, as shown at I6.v Moreover, instead of utilizing a rectangular block I'I of relatively small thickness, the modified arrangement as indicated at B utilizes a narrow block 2I of greater thickness, this block ybeing of a length substantially equal to the width of the square block I6.

By placing the pressure applying pad B with the'block 2l extending horizontally, a plurality of jacks may be applied in horizontal spaced relation, whereas if the pressure applying pad is disposed with thisJ block extending vertically; the jacks would be spaced vertically instead of horizontally.

After the first course of sheathing is secured in position, the digging of the trench progresses until it is of sufficient depth to apply a second course of panels I2 with pressure applying pads at their joints. Successive courses are added in i g to form a tier in which each pad unit has the of the panel I2 with which it is associated. This n' f projecting ends of the blocks I6 and I'I extending over the adjacent pad thereabove. The extending ends of the blocks I6 and II may be secured to the block I4 of the next uppermost pad unit by any appropriate means, such as nails or the like. The pads are therefore successively interlocked and each course is `supported from the next course above it. When utilizing pressure applying pad units as shown at B, the adjacently disposed pads are not interlocked in the manner just described. In

this case, I provide scab ties in the form of small blocks or strips 22 which are nailed or otherwise secured across the horizontal joints between the adjacently disposed panels of the adjacent courses.

In Figure 4, I have shown a modified arrangement of sheathing, wherein a horizontal course of panels I2 is provided adjacent the upper end of the trench. It will be noted that in this case the pressure applying pads, instead of being substantially square in shape, are of elongate construction. These pads, which are generally indicated at C, comprise an elongate plank 23 which is of sufcient length to enable its ends to project above and below the upper and lower edges plank has spaced lateral members 24 and 25 between which there is disposed a central member 2S which projects past the inner surfaces of the members 24 and 25 an amount substantially equal to the thickness of the panels I2; 'I'he members 23, 24, 25 and 26 are likewise assembled into a unit pressure applying pad construction f by any suitable means, such as nailing.

When utilizing this pad construction, as shown in Figure 5, the adjacent ends of the panels I2 are placed in abutment with the side surfaces of the member 26, and the rear surfaces of the members 24 and 25 overlie and engage the end margins of these panels. Jacks, as shown at 2'I and 28, are placed with their ends engaging the innermost surface of the plank 23 at areas disposed substantially at the upper and lower edges of the associated panels I2.

'Ihis arrangement is advantageous in that when pressure is applied to the pressure applying pads, pressure will be applied against the trench wall independently of the panels I2. Where a pressure applying pad is Autilzedat the vertical center line of 'a panel I2, the member 26 is omitted from the pad.

y AWhere the depth of the trench extends some distance below the top course of sheathing, a second course may be disposed along the bottom of the trench in spaced relation to the course at the top of the trench. It is preferred that this bottom course of panels should have its joints staggered with reference to the joints of the uppermost course.

The space between the top and bottom courses is then sheathed by means of vertically disposed panels 29 of similar construction to the panels I2, the ends of the vertically disposed panels overlapping the panels of the upper and lower courses. The panels 29 are secured and held in place by means of an intermediatel-y disposed wale 30 and a wale 3l which is preferably positioned so as to overlie the upper marginal portions of the panels I2 constituting the bottom course of sheathing. The wales 3D and 3l are supported by means of suitable cleats 32 on their underside, these cleats being nailed or otherwise secured tothe panels 2S.vv Adjustable jacks 33 may be placed in vertical alignment with the jacks 21 and 28 of the upper course and have their ends bearing against the wales between the panels 29 of the intermediate course.

In order to assist in locating the various sheathing panels and form a position line for pressure applying pads which are disposed intermediate the ends vof a sheathing panel, each sheathing panel may be provided intermediate its ends with indicatingmeans, such as a painted stripe 34 extending transversely of the panels.

Where particularly bad ground might be encountered at some particular point in the trench wall, I have shown in Figure 3 a construction which may be lused instead of the large area panels I2, wherein narrow planks 35 may beA placed in edge-to-edge relation, and additional pressure applying pads utilized.

Not infrequently, it so happens that where quicksand or particularly bad ground is encountered at the trench bottom, it is impossible to lay the pipe or conduit directly on the ground bottom of the trench. Under such circumstances, I provide plywood baiiles 3G which are arranged to extend transversely of the trench bottom and have their ends vertically slidable between spaced guide members 3l in the form of cleats nailed to the sheathing structure. These battles are cut out, as shown at 38, to receive the pipe or conductor therein, whereby the baflles when disposed at the proper height and secured to the sheathing structure may form a support for the pipe.

Where pipe is being laid in a particular section of a trench and there may be water in the bottom of the trench, it is desirable to prevent the flow of lwater from sections of the trench under construction into the section where the pipe is being laid. For this purpose, I provide a bulkhead extension 39 which may be associated with a balile 3B to form a barrier against the flow of water into the trench section where the pipe is being laid. It will be noted that this bulkhead is provided with a projecting portion 48 along the edge which is disposed adjacent to the upper end of the baffle, this projection being so formed as to conform to the cut-Out portion 38 of the baiile. If desired, the projecting portion may have strips 4I secured to its opposite surfaces, which will overlie the surfaces of the baffle 36 and strengthen the joint between the baffle and the bulkhead.

The use of my improved construction for sheathing an excavation wall permits the utilization of improved scaffold supporting means. Since the edge of the sheathing at the top of the r trench is formed by the aligned upper edges of the sheathing, the scaffolding, as shown in Figure 3, may be supported on hook-shaped brackets @2 having one end arranged to fit over the uppermost edge of the sheathing at the top of the trench, and its other end provided with a hook at, over which the upper end of a stirrup connecting support 44 may be disposed. The.

stirrup lil at its lower end is connected with a scaffold beam 45, on which scaiolding planking s6 is laid.

This arrangement permits the scaffold to be easily moved from one portion of the trench to another and also provides a platform for workmen which extremely safe.

From the foregoing description, it will be apparent that the herein described invention provides novel means for sheathing the walls of an excavation, such as trenches, tunnels and the like, which utilizes standardized constructional units of iight construction which may be easily moved from one location to another of the trench or other excavation; which may be easily assembled in place with a minimum expenditure of time and labor; which provides a minimum of interference with the work. of trench construction; which includes novel means for indicating the proper placing of units to secure the most eiiicient results; which .equalizes the load on the sheathing members; which permits the sheathing to be removed from the bottom upwardly as the filling of a trench progresses; which includes novel scaffold supporting means; which permits pipes, conduits and the like to be supported from the sheathing, where quicksand and bad ground prevents laying of the pipes, etc., directly on the bottom of the trench, and which embodies an arrangement which enables the sheathing members to be utilized again, these members having a very high salvage value.

It is, of course, to be understood that although I have described in detail the preferred and several modied embodiments of my invention,

the invention is not to be thus limited, but only y insofar as dened by the scope and spirit of the f-- a pended claims. o' p" I claim as my invention:

l. Means for sheathing an excavation wall comprising a plurality of horizontal courses respectively formed by panels in surface engagement with the wall and end-to-end abutting relation with the joints so formed on the respective courses in alignment, a pad member disposed over the vertical joint at each course, the pads of each set of aligned joints forming a vertical tier, and means for independently applying pressure to each of said pads for forcing it towards said wall, the pads of one course having portions engaging the pads of an adjacent course.

Means sheathing an excavation wall comprising a plurality of horizontal courses respecl'ively formed by panels in surface engagement with the wall and end-to-end abutting relation with the joints so formed on the respective courses in alignment, a pad member disposed over the vertical joint at each course, the pads of each set of aligned joints forming a vertical tier, means for independently applying pressure to each of said pads for forcing it towards said .wall, and a portion formed on each of said pads for overlying a pad of an adjacent course.

3. In a structure for sheathing the wall of a trench for a conduit or the like, panels in surface engagement with the opposed walls of the trench, means for forcing said members outwardly against the trench wall, a plurality of members extending transversely of the trench, each of said members being secured to panels of the respective walls and arranged to form a support for said conduit independent of the trench bottom, and a removable extension selectively associatable with said members to form a substantially watertight bulkhead in the bottom of the trench.

4. In a structure for sheathing trench walls, panel members disposed in end-to-end engagement against a wall of the trench, a pad in surface engagement with the engaged ends of the panels, said pad comprising a plurality of symmetrically superposed plates of decreasing width, the plate adjacent the lowermost of said plates having one end projecting past the adjacent periphery of the lowermost plate, and means engageable with the uppermost of the pad plates for applying pressure against the pad.

5. In a structure for sheathing trench walls, panel members disposed in end-to-end engagement against a wall of the trench, a pad in surface engagement with the engaged ends of the panels, said pad comprising a plurality of plates of decreasing width superposed with their longitudinal center lines lying in a common plane, the plate adjacent the lowermost of the pad plates having one end projecting beyond the periphery of the lowermost plate and its opposite end inwardly spaced from the periphery of the lowermost plate, and means engageable with the uppermost of the pad plates for applying pressure against the pad.

6. In a structure for sheathing trench walls, a pair of panel members disposed in end-to-end engagement against a Wall of the trench, a pad in surface engagement with the engaged ends of the panels, said pad comprising a plurality of symmetrically superposed plates of decreasing width, the uppermost of said plates being of greater length than width, and a plurality of pressure applying members having contact surfaces engaging the uppermost of said plates and aligned longitudinally thereof, said pad being selectively disposable as a unit in positions in ninety degree relation for obtaining vertical and horizontal alignment of the pressure applying members at the end margins of said panels.

'7. An excavation wall sheating construction comprising a pair of elongate panels placed in end-to-end abutting relation with their rear surfaces against the wall surface, a pressure distributing pad unit having a plane surface symmetrically disposed over the joint formed by the adjacent ends of said panels and engaging the forward surfaces of the panels adjacent said joint, said pad unit surface being of substantially the same length as the joint and of a width to extend outwardly on either side of the joint sufficiently to distribute pressure over relatively large areas of the ends of the panels, means for initially securing the pad unit in operative position to said panels, and means for applying pressure against said pad.

8. An excavation wall sheathing construction comprising a pair of elongate panels of laminated material placed in end-to-end abutting relation with their rear surfaces against the wall surface, a pressure distributing pad unit having a plane surface symmetrically disposed over the joint formed by the adjacent ends of said panels and engaging the forward surfaces of the panels adjacent said joint, said pad unit surface being of substantially the same length as the joint and of a' width substantially equal to its length, whereby pressure applied to the pad will be distributed over substantial marginal end areas of the panels for the full panel Width and substantially half the panel Width on each side of the joint, means for initially securing the pad unit to said panels over the joint, and means for adjustably applying pressure against said pad.

9. An excavation Wall sheathing construction comprising a pair of elongate panels placed in end-to-end abutting relation with their rear surtangular and having a length andwidth respectively corresponding substantially with the Width of said panels, means on the pad unit for determining its position over said joint, irrespective of which edge of the pad is disposed uppermost,

to effect substantially equal areas of contact on either side of the joint between the pad and tne end margins of the panels, meansfor initially securing the pad unit to said panels, and means for applying pressure against said pad,

EDMUND B. DOWD. 

